Presumably your computer is reasonably secure so only you can read your e-mail.
Are you worried about SMTP not being secure? What's an alternative way to send an e-mail password?
Inquiring minds, and all that.
The monthly password reminder is apparently controlled by a [link|http://www.yolinux.com/TUTORIALS/LinuxTutorialMailman.html|cron job] - I have no idea whether it can be configured on a per-user basis.
Cheers,
Scott.